Fork interchanger



Filed Feb. 5

DUNN

FINI

UnitedStates Patent() 3,480,167 FORK INTERCHANGER Ronald D. Varilek, Park Forest, Ill., assignor to Allis- Chalmers Manufacturing Company, Milwaukee, Wis. Filed Feb. 5, 1968, Ser. No. 703,125 Int. Cl. B66f 9/06, 9/14 U.S. Cl. 214-620 Claims ABSTRACT 0F THE DISCLOSURE An attachment with a rod mounted fork is installed on a two-bar lift truck carriage in place of the usual hook type forks. By interchanging the attachment `with rod type forks for the usual hook type forks, the lift truck user can quickly convert from hook type fork operation to rod type fork operation without altering the carriage.

This invention relates to an attachment for a two-bar type lift truck carriage where-by the hook type fork usually employed thereon can be replaced with a rod type fork.

Heretofore the lift truck industry has used both rod type forks and hook type forks, however, the latter type has become accepted as more or less a standard in the industry. The rod type fork which permits pivoting of the fork about a transverse axis has certain advantages for some of lift truck operations and therefore some lift truck users may prefer or require rod type forks.

The present invention allows a rod type fork to be installed on the two-bar type carriage customarily provided for the hook type fork. By employing this invention, the customer can easily convert from hook type forks to rod type forks and vice versa since no modification is made to the standard two-car carriage.

It is a primary object of this invention to provide a rod mounted fork attachment for a two-bar carriage which does not require modification of the latter.

It is a further object of this invention to provide a rod type fork attachment which can be interchanged with the hook type fork normally mounted on a two-bar like truck carriage.

It is a further object of this invention to provide an attachement including a rod type fork for a two-bar carriage which does not reduce the load carrying capacity of the lift truck on which it is used.

These and other objects and advantages of this invention will be apparent to those familiar with the art when the following description is read in conjunction with the drawings in which:

FIG. 1 is a front view of a lift truck carriage on which a pair of fork intechangers of the present invention are installed;

FIG. 2 is an enlarged front view of one of the interchangers shown in FIG. l; and

FIG. 3 is an end view of the lift truck carriage and interchangers shown in FIG. 1.

Referring to the drawings, the two-bar carriage 11 is a standard carriage in the lift truck industry and is normally employed to carry a hook type fork which, as is well known in the industry, is secured both to the top bar 12 and the bottom bar 13. In place of the usual two hook type forks installed on the two-bar carriage 11, a pair of fork interchanger attachment 14, of the present invention, are installed, thus converting the lift truck to rod type fork operation.

The carriage 11 is mounted on a pair of uprights 17 and 18 of the lift truck mast by four rollers 19, only two of which are shown in FIG. 3. The upper and lower bars 12, 13 are rigidly secured to one another as by the vertical and rearwardly extending flanges 21, 22 on which 3,480,167 Patented Nov. 25, 1969 ice the rollers 19 are rotatably mounted. Each of the interchangers 14 includes a support 26 which is laterally shiftable on the bars 12, 13 of carriage 11. Each support 26 includes a pair of vertically extending and horizontally spaced hangers 27, each of which has upper and lower hook portions 28 and 29 in cooperative sliding engagement with guideway portions 31, 32 on bars 12 and 13, respectively. Each support 26 also includes a rod 34, which has its laterally opposite ends press fit in bores 36, 37 in the upper hook portions 28 and additionally secured by suitable pins 38. The rod 34 pivotally mounts a rod type lift fork 41 for pivotal movement about a transverse axis 42 which is disposed above the upper bar 12. The hangers 27 are spaced apart approximately the transverse width of the upright part 43 of the fork 41 to permit the upright part 43 to engage the bars 12, 13 of the carriage 11. It will be noted that hanger 27 does not extend forwardly of the vertical part 43 of fork 41. As illustrated, the longitudinal width of hanger 27 is the same as the longitudinal width e of the vertical part 43 of the fork 41. Thus the addition of the fork interchanger does not adversely affect the center of load supported on the horizontal load support part 44 of fork` 41. Use of the interchanger of this invention does not adversely affect lift truck capacity and does not require any moditication of the standard two-bar carriage.

Those familiar with the lift truck art will readily appreciate that the fork interchanger of this invention permits a standard lift truck with two-bar carriage to lbe converted to a rod type fork operation in a quick and inexpensive manner. The lift truck, after conversion, can be converted back to a rod type fork operation with equal ease.

1. A fork interchanger comprising a support having a pair of vertically extending and horizontally spaced hangers each having upper and lower hook portions that slidably engage upper and lower guideways on a vertically movable twobar type lift truck carriage and a horizontally disposed rod extending between and connected to said upper hook portions of said hangers and a rod type fork having an upright part disposed between said hangers and connected at its upper end to said rod and a horizontally disposed support part extending forwardly from the lower end of said upright part, said hangers being spaced apart approximathely the transverse width of said upright part of said fork and said interchanger being constructed so that said upright part engages said carriage when the interchanger is installed thereon.

2. The invention of claim 1 wherein said fork hangers do not extend forwardly beyond said upright part of said fork.

3. The invention of claim 1 wherein said rod is rigidly connected to said hangers and said fork is pivotally connected to said rod.

4. The invention of claim 3 wherein said upper hook portions and rod are disposed above the upper guideway of said carriage when installed thereon.

5. The invention of claim 4 wherein said hangers do not extend forwardly beyond said upright part of said fork.

UNITED STATES PATENTS References Cited 2,598,566 5/1952 Lehmann. 2,621,822 12/1952 Melin 214-730 (Other references on following page) 3 4 Blatz 214-730 3,353,698 11/1967 Link 214-730 Allen. Gibson 214-730 GERALD M. FORLENZA, Primary Examiner Schenkelberger 214-730 Cavanagh 214 730 X R. I. SPAR, Asslstant Exarnmer Shaffer 214-730 5 U S @1 X R Hansen 214-730 0-1050 UNITED STATES rATENT OFFICE 56g CERTIFICATE OF CORRECTION Patent No. 3,1480,167 Dated November 25, 1969 mfentods) Ronald D. `Varilek It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

f- Column 2, between lines 33 and 3LP, insert the following I paragraph The embodiments of the invention for which an exclusive property or privilege is claimed are defined as follows: --5 line 50, mathely" should read mately and line 55, cancel "fork".

SIGNED AND SEALED JUN 2 1970 45ML) new Emd M nach I" WILLIAM E. www. JR. nesting Officer Comissioner of Patents 

